An Unusual Case of Cardiac Arrest

A 67-year-old man is transferred to our institution from an outside facility after suffering a witnessed cardiac arrest at home. He has a medical history of hypertension, dyslipidemia, coronary atherosclerosis, prior inferior non-ST-segment elevation myocardial infarction, and sick sinus syndrome post dual-chamber pacemaker implantation.

The patient initially reported sudden onset of chest pain described as "a brick on my chest" and collapsed a few minutes later. He was resuscitated promptly by his son. Upon arrival of emergency medical services, he was found to be in ventricular fibrillation. A 200 J asynchronous shock was delivered, after which he developed pulseless electrical activity. Return of spontaneous circulation was achieved after a total of 28 minutes of appropriate cardiopulmonary resuscitation. The patient arrived comatose at an outside facility approximately 35-40 minutes after losing consciousness. An electrocardiogram was obtained and is shown in Figure 1. His laboratory results were consistent with mild lactic acidosis (lactic acid = 3.6 mmol/L), normal renal function, and a cardiac troponin I level of 0.035 ng/mL. A limited transthoracic echocardiogram showed no significant wall motion abnormalities, no significant valvular lesion, and a new small pericardial effusion. The patient was emergently transferred to the cardiac catheterization laboratory at our hospital. Coronary angiograms of his left and right coronary artery are shown in Videos 1 and 2, respectively.

Figure 1

Figure 1
Electrocardiogram obtained after the return of spontaneous circulation.

Video 1

Coronary angiogram of the left coronary artery from a right anterior oblique view with cranial angulation. There is mild non-obstructive coronary disease of the left anterior descending artery.

Video 2

Coronary angiogram of the right coronary artery from an anteroposterior view with cranial angulation. Note the significant ostial posterior descending artery lesion without the presence of thrombus and Thrombolysis in Myocardial Infarction 3 flow throughout the vessel.

Based on the clinical history and diagnostic tests described, what would be the next best step in the management of this patient?

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